So far, a micropattern recorded in the form of a volume hologram has been as fine as about 100 μm. In some relief holograms, micropatterns as fine as about 30 μm have been recorded in the form of holograms.
When a visually unidentifiable pattern such as a microtext pattern was recorded in the prior art, a pattern fabricated with a printing film or the like was used as an object for holographic recording (Patent Publication 1), or a pattern fabricated with a printing film or the like was brought into close contact with a holographic recording material, and the holographic recording material was deactivated in a pattern form to form a hologram pattern (Patent Publication 2).